1. Field of the Invention
The present invention is directed toward the art of toner cartridges and, more particularly, to an improved toner stirring mechanism for such toner cartridges.
2. The Prior Art
Generally, in an image forming apparatus such as a photographic copying machine, an electro-photographic printer (ex. LED printer, laser beam printer), and an electro-photographic facsimile machine, an electro-photographic word processor, and the like.
A developing device for forming a toner image on the photosensitive drum is disposed around the photosensitive drum. The developing device includes a toner hopper for supplying toner, and a toner cartridge detachably connected to the toner hopper. When the toner in the toner cartridge is depleted, the toner cartridge can be replaced with a new one.
The toner cartridge generally includes a toner container for storing the toner, the toner container having an opening in it that allows the toner to be discharged into the toner hopper. These types of toner cartridges may also include one or more stirring rods (or stirring plates) disposed inside the toner container. In these types of toner cartridges, the stirring rod is often made longer than the length of the container so as to allow at least one end of the stirring rod to extend outside the side walls of the toner cartridge. The stirring rod is typically driven by a force externally transmitted, by way of a motor disposed outside of the toner cartridge, to a stirring gear which supports one end of the stirring rod, and the stirring gear is supported by the toner container. The stirring gear can be a helical gear formed of resin material such as POM, and is attached to the toner container by snap-fitting. As for the transmission of the driving force to the stirring gear, the driving force from the motor is transmitted to the helical gear portion of the stirring gear by way of a gear train or the like.
In the above-described toner cartridge, the toner container must be at least as wide as the widest portion of the stirring rod. Therefore in order to rotatably support the stirring rod and to prevent the toner from leaking out of the toner cartridge, bearing portions must be fitted to each end of the stirring rod. Additionally, the conventional toner cartridge generally uses one stirring rod or stirring plate for stirring the toner, yet the stirring rod has a smaller contacted area with the toner so as to produce the bad mixed toner, but the stirring plate has a larger contacted area with the toner, so as to increase the stirring resistance, and the stirring rod is directly connected to the stirring gear so as to fail to provide a multi-directional reciprocation due to the stirring rod or stirring plate.
It is an object of the present invention to provide a toner cartridge with a stirring mechanism, which is well mixed with toner contained in a toner container, thereby blocking of the toner can be prevented and fluidity of the toner also can be improved by the movement of the toner stirring mechanism in the toner container, and stable toner flow to a developing device of is accomplished.
In accordance with one aspect of the present invention, which provides a toner cartridge comprising a toner container, a toner stirring mechanism and a transmission mechanism. The toner container comprises two side walls and a chamber defined between two side walls for containing toner. The toner stirring mechanism comprises a stirring member having a grating shape defined with a predetermined contact area for stirring the toner, and a pair of swing rods each having a upper end pivotally connected on each of the side walls of the toner container, and a lower end thereof pivotally connected to each of two sides of the stirring member. The transmission mechanism comprises a camshaft being mounted on one side wall of the toner container and having an inside end matched with one swing rod of the toner stirring mechanism, and a stirring gear integrally formed on an outside end of the camshaft for driving the camshaft to rotate.